The Structuring Role of Submerged Macrophytes in Lakes

ISBN-13: 9780387982847 / Angielski / Twarda / 1997 / 427 str.

Erik Jeppesen; M. Sondergaard; U. Sommer

Opis

Submerged macrophytes have been the object of intensive research, and a large body of literature exists on their growth, reproduction, and physiology. Several studies have focused on the interactions between submerged macrophytes and other autotrophic components and the impact of the plants on the dynamics of nutrients, dissolved organic and inorganic carbon, oxygen, and pH. Comparatively few studies have dealt with the ability of submerged macrophytes to modulate the structure and dynamics of pelagic and benthic food webs. Recently, however, the amount of research into the structuring role of submerged macrophytes in food webs has markedly increased, and the results obtained so far suggest that sub- merged macrophytes are of significant importance for the food web interactions and environmental quality of lakes, even at relatively low areal plant coverage. For example, plants affect the interactions between predacious, planktivorous, and benthivorous fish and between fish and invertebrates, including key organisms such as large zooplankton and snails. Changes in these interactions in turn may have cascading effects on the entire food web in both the pelagial and the littoral zone. To provide a forum for discussion of recent results in this growing field of research and to define future research needs, a workshop was held on 16 to 20 June, 1996, at the Freshwater Centre in Silkeborg, Denmark. The present book is a result of the workshop. It is divided into three parts.

Spis treści

Section 1. General Themes.- 1. Fish-Habitat Interactions Mediated via Ontogenetic Niche Shifts.- 2. Influence of Submerged Macrophytes on Trophic Interactions Among Fish and Macroinvertebrates.- 3. Complex Fish-Snail-Epiphyton Interactions and Their Effects on Submerged Freshwater Macrophytes.- 4. Interactions Between Periphy ton, Nonmolluscan Invertebrates, and Fish in Standing Freshwaters.- 5. Impact of Submerged Macrophytes on Fish-Zooplankton Interactions in Lakes.- 6. Impact of Submerged Macrophytes on Phytoplankton in Shallow Freshwater Lakes.- 7. Role of Submerged Macrophytes for the Microbial Community and Dynamics of Dissolved Organic Carbon in Aquatic Ecosystems.- 8. Impact of Herbivory on Plant Standing Crop: Comparisons Among Biomes, Between Vascular and Nonvascular Plants, and Among Freshwater Herbivore Taxa.- 9. Interactions Between Grazing Birds and Macrophytes.- 10. Effects of Submerged Aquatic Macrophytes on Nutrient Dynamics, Sedimentation, and Resuspension.- Section 2. Case Studies.- 11. Macrophyte Structure and Growth of Bluegill (Lepomis macrochirus): Design of a Multilake Experiment.- 12. Vertical Distribution of In-Benthos in Relation to Fish and Floating-Leaved Macrophyte Populations.- 13. Horizontal Migration of Zooplankton: Predator-Mediated Use of Macrophyte Habitat.- 14. Changing Perspectives on Food Web Interactions in Lake Littoral Zones.- 15. Bacterioplankton and Carbon Turnover in a Dense Macrophyte Canopy.- 16. Cascading Effects on Microbial Food Web Structure in a Dense Macrophyte Bed.- 17. Abundance, Size, and Growth of Heterotrophic Nanoflagellates in Eutrophic Lakes with Contrasting Daphnia and Macrophyte Densities.- 18. What Do Herbivore Exclusion Experiments Tell Us? An Investigation Using Black Swans (Cygnus atratus) and Filamentous Algae in a Shallow Lake.- 19. Switches Between Clear and Turbid Water States in a Biomanipulated Lake (1986-1996): The Role of Herbivory on Macrophytes.- 20. Macrophyte-Waterfowl Interactions: Tracking a Variable Resource and the Impact of Herbivory on Plant Growth.- 21. Influence of Macrophyte Structure, Nutritive Value, and Chemistry on the Feeding Choices of a Generalist Crayfish.- 22. Concordance of Phosphorus Limitation in Lakes: Bacterioplankton, Phytoplankton, Epiphyte-Snail Consumers, and Rooted Macrophytes.- 23. Sources of Organic Carbon in the Food Webs of Two Florida Lakes Indicated by Stable Isotopes.- 24. Importance of Physical Structures in Lakes: The Case of Lake Kinneret and General Implications.- 25. Clear Water Associated with a Dense Chara Vegetation in the Shallow and Turbid Lake Veluwemeer, The Netherlands.- 26. Alternative Stable States in Shallow Lakes: What Causes a Shift?.- 27. Clear and Turbid Water in Shallow Norwegian Lakes Related to Submerged Vegetation.- 28. Macrophytes and Turbidity in Brackish Lakes with Special emphasis on the Role of Top-Down Control.- Section 3. Interdisciplinary Discussions.- 29. Structuring Role of Macrophytes in Lakes: Changing Influence Along Lake Size and Depth Gradients.- 30. Nutrient-Loading Gradient in Shallow Lakes: Report of the Group Discussion.- 31. Alternative Stable States.